Jump to content

Entry for September 2018's Guitar Of The Month is open!
ENTER HERE!

verhoevenc

Double dye stabilizing wood

Recommended Posts

So I have a TON of new info to add after these experiments and talking with Curtis (owner of the cactus juice brand) that I'll get up here later. However, I want to put out one big warning: Do NOT use your home oven. The fumes put off during curing aren't toxic... but they're by no means healthy and something one should strive to breath. I have some spillover that really smelled bad when the temp was cranked to cook actual food... needless to say that was put to a stop until I can do some heavy duty cleaning.

Toaster ovens are fine for small pieces... but I guess I'll be scouring craigslist for a cheap beater oven to keep out in the barn and roll outside for curing.

Chris

Share this post


Link to post
Share on other sites

Here's the low-down Curtis (cactus juice brand owner) gave me after reading this thread. If I have stuff to add I'll make it clear that they're my additions:

  • Soak only on first color will typically give you more of an organic dye look.  If I was soaking those pieces, I would expect to need to soak 10-12 hours probably.  What happens with soaking only is the wood picks up the first color through natural capillary action in the more porous portions of the wood.  Then, when you cure, those become impervious.  Then the second color with full vacuum draws the second color into the remainder of the wood.  The first color, if soaking, should be your highlight or secondary color.  The final full vacuum color will be your primary color. (Chris: this makes sense given that my second color pulls didn't really take that well)
  • You are going REAL short on your second vacuum time if I read the write up correctly.  I believe it said you were only pulling vac for 2 hours.  Even with pen blanks, I am almost always needing to pull vac for 6-8 hours, sometimes even more... The more air you remove, the more resin you get back into the wood and the better the material will be stabilized. (Chris: After talking more with him about how I was getting color into the center he agrees that you can get full penetration with a shorter vacuum, but to get the fully saturated- and I'm guessing additional structural benefits- one should pull longer. Therefore, I'll be pulling much longer vacuums in the future especially for things like making fretboard material from stuff that would otherwise not work for that as well as for tops of questionable stability that I may want to use on chambered instruments)
  • On the same topic as above, if you are not pulling full vacuum for your elevation, your bubbles will stop much sooner than they would with deeper vacuum.  That is what makes me ask about the level of vacuum you are pulling.  I assume you can see into your chamber.  If not, you really need to be able to since the only way you will know when your blanks are properly vacuumed is when the bubbles stop coming out of the material.  Again, though, if you are not pulling full vac for your elevation, even if the bubbles stop at 2 hours, you have not completed the job of stabilizing.
  • The shelf life of activated Cactus Juice is 1 year, not sure if you knew that but saw where you mentioned it has a shelf life so I thought I would point that out.
  • Dry the wood at 220° F for a MINIMUM of 24 hours.  With bigger pieces, it will need longer than that.  The only way to know for sure is by weight.  Weigh the blanks first, then cook for 24 hours.  then weight again and put them back in and cook for a couple more hours.  Keep repeating this until you get two consecutive weight readings that are identical and your wood will be 0% moisture content.  You can probably do this one time for each different size piece you are doing to get a baseline, then when doing a similar size piece in the future, just dry the the same time as the baseline.  Any moisture that is in your wood will give you grief.  First, it causes considerable bleed out when curing.  Second, moisture occupies space in the wood that you could be filling with resin.  As above, the whole objective of stabilizing is to saturate the wood.
  • Cure your blanks at 190-200° F.  Make sure and use an oven thermometer as oven dials are notoriously inaccurate.

Hope this helps.

Again, as I'm learning more about this though I'm learning more about the safety precautions I SHOULD have been taking. I'll be buying elbow-length gloves next time I experiment and won't be doing any more stabilizing until I get a "shop oven." Until then... off to go try and clean my current oven real good.

Chris

Share this post


Link to post
Share on other sites

OK, well here's where the journey ends for at least the near future. This is how the spalted maple turned out in the end. Looks like the longer green pull did in fact benefit this pieces as the spalted areas resisted the short blue pull... but some of them were no match for the longer green! It's hard to tell just how cool this one is from a low-grit sanded pic... but it shines more in person and the ink lines which are hard to see within the green are a lot cooler.

IMG_9963.thumb.JPG.ae98ad24d9ff5ebf0bdb4d9ed1054d10.JPG

I will also say that I was a little surprised when I resawed them... the buckeye cupped a good amount along it's length??? Away from one another. Didn't really expect that... but it's thin enough material that it won't be of any consequence. Sorry, no pics, didn't sand the inner surfaces so they'd have sucked to see bookmatched right now.

Chris

Share this post


Link to post
Share on other sites

The cupping is a surprise! I wonder if the removal of moisture and replacement with resin causes the internal tension but holds it back by virtue of the infusion?

Share this post


Link to post
Share on other sites

Sorry, I guess cupping would an across the width, what I meant to say was 'bow' as it's along the length... does that distinction even matter in burls? Lol

Chris

Share this post


Link to post
Share on other sites

Ah, I just re-read and saw "along the length". Bowing, yes.

I put some thought into why this might happen in a burl today, and all I can think of is that it might be the infusion process itself since there is little to no consistent grain with respect to the heart of the tree that would induce "proper" bowing. It might just look like bowing? I take it that the resin cure is (outside to inside?) which sounds liable to building in some minor imbalance stresses. Buckeye is chowdery soft wood like Haapa, so I guess that it'll easily be pulled around by those if released by resawing.

I'm guessing really. Your resin guy might yield better answers. I'd be interested in hearing them myself.

Share this post


Link to post
Share on other sites

You're probably on the money there, Chris. Quite possibly the bowing might have had nothing to do with what we normally represent as a bow in straight timber and some other factor inducing it. Like you said....burls don't fall into the category of normal board warping terms.

It might be worthwhile looking at the process, and whether any stages may express bias towards say, one side drying quicker than the other  through environmental differences (airflow, moisture, heat, light, gravity) or other potential sources of inequality.

Share this post


Link to post
Share on other sites

I've got my money on knowing why it happened. Here's what I did.

1- Pulled it out of the oven... got really excited

2- Went straight to the sander to level the faces (more heat)

3- Went straight to the resaw and cut it down the center thus releasing the inner core to the cold in a rather quick and drastic fashion

I'm sure I could avoid any and all non-permanent warping by simply adding some patience hahaha.

Chris

  • Like 2

Share this post


Link to post
Share on other sites

Quick note about the last post: thought I already posted this but all cupping along length went away with no effort when snickered for a day. Maybe another benefit of the plasticized nature of the finished product?

Chris

Share this post


Link to post
Share on other sites

I also meant to post these as they've been done for a good long while...

this one sat with its inside edge in a black bath of like 1.5" deep for about 8 hours. The capillary action really wicked the black up far. Second bath with vacuum for 8 hours was green. Not sure I like the darkness the black gave on this one very much.

 

Next one is probably my favorite so far! 8 hour bath in purple. Second bath with 8 hours of vacuum was red.

IMG_9964.thumb.JPG.b1dd730fd62b6b2e7d4ad98bacd2acea.JPGIMG_9965.thumb.JPG.83cc6ceee52fe77213ac68eaedf04db5.JPG

As per current process, both initial baths were purely soaking baths, no vacuum, and obviously the color of the first bath was cured and sanded prior to the second. Pics are of both faces.

Best,

Chris

  • Like 2

Share this post


Link to post
Share on other sites

The two I'm doing this weekend should be pretty fun too. Two more buckeye burl billets. So far I've soaked both in just clear cactus juice... but I didn't have enough so I actually came back a few hours later and the 'bath' was bone dry as they'd absorbed everything... so it's tough to know just how this will work this time! Basically I put both on top of each other in the tub and filled it to say... 1/16"-1/8" above the wood's surface.

Plan is then to vacuum one in red and the other in, probably, purple. I want to see how the colors react with the "clear" stabilized areas.

Chris

Share this post


Link to post
Share on other sites

Expensive experiments, Chris. At least, from my perspective anyway. What sort of end uses are these meeting? That purple is simply incendiary, and wish it were simple and/or cheap to get those sort of results this side of the pond. You guys get all of the toys. I've been shopping for a radius router bit set and that's a bank-breaker as it stands! Yeeps.

Share this post


Link to post
Share on other sites

I will be using my first piece on a build in the next batch. It will only best a detail section about 3"x4" but will use that really crazy non-top piece of burl from earlier. Once I get a feel for it in this small use I'll probably be bolded to use one of my full tops.

I plan to build with them just like any other top material... or just stock-pile like I'm want to do hahaha.

I have a giant poplar burl I'm drying that... 2 years from now... will be screaming for stabilization.

Chris

Share this post


Link to post
Share on other sites

These are absolutely crazy cool. A guitar top made with this process seems like the kind of thing that could really help differentiate your work even further from other boutique builders.

Share this post


Link to post
Share on other sites

Alpher instruments (with the help of Californiawoods.com) sure did!

heres the clear/red experiment:

A3E8E0A0-4600-496F-A32C-1D0E190BC90B.thumb.jpg.41d3514f02864491a827ec79fb2a23cf.jpg

I'm thinking I need to add more dye so my colors are richer. The blue was more green, the red was more pink. I like the results, but they weren't what I expected.

I'm also tempted to think that over use my blue has gotten less blue (see earlier examples, same tub of juice). Wonder if that happens? Or maybe the piece I chose was just something that wanted to mess with the blue? Oh well, experimentation! Next time I buy I'm gunna really saturate my blue and see how that works out.

Ive definitely learned (from pen blanks I'm doing at the same time for more tests) that you REALLY gotta beef up the black juice!

Chris

Share this post


Link to post
Share on other sites

Here's that "the first place I'll be using the stuff" reference I made above:

IMG_9973.JPG.10459bb1000398cd5922a4932b4730ec.JPG

I put this body blank together awhile ago so it's ready and waiting when the new batch starts later this summer.

Chris

Share this post


Link to post
Share on other sites

I resawed open some of the billets I posted above and it's interesting to see how different some are on the inside. The one that was supposed to be blue, but took on a more green tone really opened up to the idea of blue on the inside! Also, you can really tell I did a clear-juice-soak first as well:

IMG_9967.thumb.JPG.1428981ae1986f4850fe4340f1addb41.JPG

The other one where I did some black-soak work before a purple and hreen mix also came alive a bit more inside... less deadened by the black:

IMG_9966.thumb.JPG.a90eebd3ffa02304f5db84fdd06b6862.JPG

Fun stuff. Got some maple burl in the mail yesterday. Looking forward to messing with that.
Chris

Share this post


Link to post
Share on other sites

It looks like you could treat the wood in the rough and then work it and finish sand it afterwords...and possibly get cleaner, brighter colors in doing so...(?)

SR

Share this post


Link to post
Share on other sites

Not sure I follow. I generally am not doing any sanding of the surfaces prior to the first soak (I'm going to have to sand them before the vacuum soak anyways, so why waste thickness).

Chris

Share this post


Link to post
Share on other sites

Well, it sounds like you are doing what I was theorizing about anyway. Your re-sawing pics above seem to indicate that the colors may be a bit cleaner under the surface, so I was suggesting taking advantage of that during a build. If your plan was always to soak raw stock or rough cut stock first and then work it then that is what is going to happen anyway. Come to think of it, I can't think of any way to do this to a finished or nearly finished piece...unless you were making a one piece body.

Does the process affect gluing - strength of bond- in any way?

SR

Share this post


Link to post
Share on other sites

Hmmm... so the biggest issue I seem to be running into with large pieces is warping! Quite frustrating! They seem to want to warp at two times:

1- they like bowing, along the length, up and away from the oven coil at the bottom when doing the initial drying. This makes me think I should weight them down when drying and/or wrap them in foil to make the heating more even. Some folks say air flow helps but I'm not buying yet another oven ?

2- They love to warp, again bowing along the length, once resawn. The billet may be perfectly flat but the second it comes off the saw the centers of the board act like they're magnet and fly away from one another. I'm thinking perhaps the answer here is to resaw first and then stabilize? If I can keep them flat in the oven I think this may be the winning solution.

Side note: I find it really strange that these boards like bowing along the length. That's pretty much the least common type of warping you see naturally. I can't help wonder what's driving this? This also makes me scared to map tops thicker than the 1/8" ones I have been so far. Those seem to calm down a bit once stickered flat awhile. I have one 1/4" top under weight right now but I'm leery of success.

Chris

Share this post


Link to post
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now

×